[LR1110] Added configurable LR-FHSS grid spacing

src/modules/LR11x0/LR1110.cpp

@@ -31,9 +31,9 @@ int16_t LR1110::beginGFSK(float freq, float br, float freqDev, float rxBw, int8_
   return(state);
 }
 
-int16_t LR1110::beginLRFHSS(float freq, uint8_t bw, uint8_t cr, int8_t power, float tcxoVoltage) {
+int16_t LR1110::beginLRFHSS(float freq, uint8_t bw, uint8_t cr, bool narrowGrid, int8_t power, float tcxoVoltage) {
   // execute common part
-  int16_t state = LR11x0::beginLRFHSS(bw, cr, tcxoVoltage);
+  int16_t state = LR11x0::beginLRFHSS(bw, cr, narrowGrid, tcxoVoltage);
   RADIOLIB_ASSERT(state);
 
   // configure publicly accessible settings

src/modules/LR11x0/LR1110.h

@@ -58,13 +58,14 @@ class LR1110: public LR11x0 {
       \param freq Carrier frequency in MHz. Defaults to 434.0 MHz.
       \param bw LR-FHSS bandwidth, one of RADIOLIB_LR11X0_LR_FHSS_BW_* values. Defaults to 722.66 kHz.
       \param cr LR-FHSS coding rate, one of RADIOLIB_LR11X0_LR_FHSS_CR_* values. Defaults to 2/3 coding rate.
+      \param narrowGrid Whether to use narrow (3.9 kHz) or wide (25.39 kHz) grid spacing. Defaults to true (narrow/non-FCC) grid.
       \param power Output power in dBm. Defaults to 10 dBm.
       \param tcxoVoltage TCXO reference voltage to be set. Defaults to 1.6 V.
       If you are seeing -706/-707 error codes, it likely means you are using non-0 value for module with XTAL.
       To use XTAL, either set this value to 0, or set LR11x0::XTAL to true.
       \returns \ref status_codes
     */
-    int16_t beginLRFHSS(float freq = 434.0, uint8_t bw = RADIOLIB_LR11X0_LR_FHSS_BW_722_66, uint8_t cr = RADIOLIB_LR11X0_LR_FHSS_CR_2_3, int8_t power = 10, float tcxoVoltage = 1.6);
+    int16_t beginLRFHSS(float freq = 434.0, uint8_t bw = RADIOLIB_LR11X0_LR_FHSS_BW_722_66, uint8_t cr = RADIOLIB_LR11X0_LR_FHSS_CR_2_3, bool narrowGrid = true, int8_t power = 10, float tcxoVoltage = 1.6);
 
     // configuration methods
 

src/modules/LR11x0/LR1120.cpp

@@ -31,9 +31,9 @@ int16_t LR1120::beginGFSK(float freq, float br, float freqDev, float rxBw, int8_
   return(state);
 }
 
-int16_t LR1120::beginLRFHSS(float freq, uint8_t bw, uint8_t cr, int8_t power, float tcxoVoltage) {
+int16_t LR1120::beginLRFHSS(float freq, uint8_t bw, uint8_t cr, bool narrowGrid, int8_t power, float tcxoVoltage) {
   // execute common part
-  int16_t state = LR11x0::beginLRFHSS(bw, cr, tcxoVoltage);
+  int16_t state = LR11x0::beginLRFHSS(bw, cr, narrowGrid, tcxoVoltage);
   RADIOLIB_ASSERT(state);
 
   // configure publicly accessible settings

src/modules/LR11x0/LR1120.h

@@ -58,13 +58,14 @@ class LR1120: public LR11x0 {
       \param freq Carrier frequency in MHz. Defaults to 434.0 MHz.
       \param bw LR-FHSS bandwidth, one of RADIOLIB_LR11X0_LR_FHSS_BW_* values. Defaults to 722.66 kHz.
       \param cr LR-FHSS coding rate, one of RADIOLIB_LR11X0_LR_FHSS_CR_* values. Defaults to 2/3 coding rate.
+      \param narrowGrid Whether to use narrow (3.9 kHz) or wide (25.39 kHz) grid spacing. Defaults to true (narrow/non-FCC) grid.
       \param power Output power in dBm. Defaults to 10 dBm.
       \param tcxoVoltage TCXO reference voltage to be set. Defaults to 1.6 V.
       If you are seeing -706/-707 error codes, it likely means you are using non-0 value for module with XTAL.
       To use XTAL, either set this value to 0, or set LR11x0::XTAL to true.
       \returns \ref status_codes
     */
-    int16_t beginLRFHSS(float freq = 434.0, uint8_t bw = RADIOLIB_LR11X0_LR_FHSS_BW_722_66, uint8_t cr = RADIOLIB_LR11X0_LR_FHSS_CR_2_3, int8_t power = 10, float tcxoVoltage = 1.6);
+    int16_t beginLRFHSS(float freq = 434.0, uint8_t bw = RADIOLIB_LR11X0_LR_FHSS_BW_722_66, uint8_t cr = RADIOLIB_LR11X0_LR_FHSS_CR_2_3, bool narrowGrid = true, int8_t power = 10, float tcxoVoltage = 1.6);
 
     // configuration methods
 

src/modules/LR11x0/LR11x0.cpp

@@ -98,11 +98,14 @@ int16_t LR11x0::beginGFSK(float br, float freqDev, float rxBw, uint16_t preamble
   return(RADIOLIB_ERR_NONE);
 }
 
-int16_t LR11x0::beginLRFHSS(uint8_t bw, uint8_t cr, float tcxoVoltage) {
+int16_t LR11x0::beginLRFHSS(uint8_t bw, uint8_t cr, bool narrowGrid, float tcxoVoltage) {
   // set module properties and perform initial setup
   int16_t state = this->modSetup(tcxoVoltage, RADIOLIB_LR11X0_PACKET_TYPE_LR_FHSS);
   RADIOLIB_ASSERT(state);
 
+  // set grid spacing
+  this->lrFhssGrid = narrowGrid ? RADIOLIB_LR11X0_LR_FHSS_GRID_STEP_NON_FCC : RADIOLIB_LR11X0_LR_FHSS_GRID_STEP_FCC;
+
   // configure publicly accessible settings
   state = setLrFhssConfig(bw, cr);
   RADIOLIB_ASSERT(state);
@@ -418,8 +421,8 @@ int16_t LR11x0::startTransmit(const uint8_t* data, size_t len, uint8_t addr) {
 
   if(modem == RADIOLIB_LR11X0_PACKET_TYPE_LR_FHSS) {
     // in LR-FHSS mode, the packet is built by the device
-    // TODO add configurable grid step and device offset
+    // TODO add configurable device offset
-    state = lrFhssBuildFrame(this->lrFhssHdrCount, this->lrFhssCr, RADIOLIB_LR11X0_LR_FHSS_GRID_STEP_FCC, true, this->lrFhssBw, this->lrFhssHopSeq, 0, const_cast<uint8_t*>(data), len);
+    state = lrFhssBuildFrame(this->lrFhssHdrCount, this->lrFhssCr, this->lrFhssGrid, true, this->lrFhssBw, this->lrFhssHopSeq, 0, const_cast<uint8_t*>(data), len);
     RADIOLIB_ASSERT(state);
 
   } else {

src/modules/LR11x0/LR11x0.h

@@ -796,10 +796,11 @@ class LR11x0: public PhysicalLayer {
       \brief Initialization method for LR-FHSS modem.
       \param bw LR-FHSS bandwidth, one of RADIOLIB_LR11X0_LR_FHSS_BW_* values.
       \param cr LR-FHSS coding rate, one of RADIOLIB_LR11X0_LR_FHSS_CR_* values.
+      \param narrowGrid Whether to use narrow (3.9 kHz) or wide (25.39 kHz) grid spacing.
       \param tcxoVoltage TCXO reference voltage to be set.
       \returns \ref status_codes
     */
-    int16_t beginLRFHSS(uint8_t bw, uint8_t cr, float tcxoVoltage);
+    int16_t beginLRFHSS(uint8_t bw, uint8_t cr, bool narrowGrid, float tcxoVoltage);
 
     /*!
       \brief Reset method. Will reset the chip to the default state using RST pin.
@@ -1594,7 +1595,7 @@ class LR11x0: public PhysicalLayer {
     uint16_t preambleLengthGFSK = 0;
 
     // cached LR-FHSS parameters
-    uint8_t lrFhssCr = 0, lrFhssBw = 0, lrFhssHdrCount = 0;
+    uint8_t lrFhssCr = 0, lrFhssBw = 0, lrFhssHdrCount = 0, lrFhssGrid = 0;
     uint16_t lrFhssHopSeq = 0;
 
     float dataRateMeasured = 0;

src/protocols/PhysicalLayer/PhysicalLayer.h

@@ -62,6 +62,9 @@ struct LrFhssRate_t {
 
   /*! \brief Coding rate */
   uint8_t cr;
+
+  /*! \brief Grid spacing */
+  bool narrowGrid;
 };
 
 /*!
@@ -74,6 +77,9 @@ union DataRate_t {
 
   /*! \brief Interpretation for FSK modems */
   FSKRate_t fsk;
+
+  /*! \brief Interpretation for LR-FHSS modems */
+  LrFhssRate_t lrFhss;
 };
 
 /*!